Continuity of the Value Function for Deterministic Optimal Impulse Control with Terminal State Constraint

Deterministic optimal impulse control problem with terminal state constraint is considered. Due to the appearance of the terminal state constraint, the value function might be discontinuous in general. The main contribution of this paper is the introduction of an intrinsic condition under which the value function is continuous. Then by a Bellman dynamic programming method, the corresponding Hamilton-Jacobi-Bellman type quasi-variational inequality (QVI, for short) is derived for which the value function is a viscosity solution. The issue of whether the value function is characterized as the unique viscosity solution to this QVI is carefully addressed and the answer is left open challengingly.Comment: 29 page

Manipulating Atom-Cavity Interactions with Configurable Atomic Chains

We investigate a ring cavity comprising two degenerate counter-propagating modes coupled to a one-dimensional atomic chain, leading to bidirectional light scattering. The spatial configuration of the atomic chain, described by a structure factor, plays a crucial role in manipulation of the atom-cavity interactions and formation of the collective excitation modes. Remarkably, we observe that a cavity dark mode is induced when the atomic spacing is an integer multiple of half-wavelength. The nodes of this standing-wave dark mode align precisely with the atomic positions, enabling intracavity field conversion without free space scattering. By adjusting the configuration of the atomic chain, we realize optical mode conversion with almost no photon loss and a broad tuning range, making it suitable for various practical applications in quantum technologies

A study of translation of Viver, from Yu Hua

Orientador: Érica Luciene Alves de LimaDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Estudos da LinguagemResumo: O objetivo da presente dissertação é analisar a tradução do romance de Yu Hua, escrito originalmente em chinês, intitulado ?? (1993). A principal tradução a ser trabalhada é a versão brasileira, intitulada Viver (2008), traduzida por Márcia Schmaltz, mas também será trazida para a discussão a versão em inglês To Live (2003), traduzida por Michael Berry. Para o estudo, inicialmente é feita uma breve comparação entre algumas teorias de tradução, tanto as da China quanto as do Ocidente, enfatizando aspectos importantes e mudanças teóricas especialmente da época moderna. Em seguida, são apresentadas as características da época literária à qual o romance pertence e os aspectos principais da história e das personagens, primordiais para a análise da tradução. Por fim, são apresentados os tradutores e o contexto de publicação das traduções e analisados trechos de cada um dos livros, coletados e selecionados pelo método do cotejo. Os casos mais emblemáticos das traduções analisadas englobam a tradução de palavrões e repetição de palavras, além de duas expressões chinesas típicas, com certos formatos peculiares ¿ a reduplicação e o provérbio ¿ os quais conferem certa coloquialidade à linguagem utilizada pelo original. O resultado das análises mostrou que a tradução para o português apresenta alguns cuidados com a escolha vocabular, evitando palavrões e termos coloquiais. Por outro lado, mostra grande preocupação em encontrar estratégias para a tradução da reduplicação e do provérbio, trazendo aspectos característicos da língua portuguesa e, ao mesmo tempo, tentando apresentar aspectos culturais da China, o que nem sempre ocorre na tradução para o inglêsAbstract: This research aims to analyze the translation of the novel ?? (1993) from a Chinese author called Yu Hua. The main translation to be analyzed is the Brazilian version translated by Márcia Schmaltz, Viver (2008), but the English translation To Live (2003), translated by Michael Berry will also be presented. The search starts with a brief comparison between some translation theories in China and in the Occident (Western Europe), tracing the most influent view in Translation Studies specially during the modern era. Next, the characteristics of the literary period to which the novel belongs, and the main aspects of the history and the characters of the novel are presented, to help with the analysis of the translation. Finally, we present the translators and the context of publication of the translations, and analyzed excerpts from each book, collected and selected by the comparative analysis method. The most emblematic cases of translations studied include the translation of curse word and repetition of words, as well as two typical Chinese expressions, generally with certain peculiarity in their forms - reduplication and proverb - which give a certain colloquiality to the language used by the original. The results of the analyzes showed that the translation into Portuguese gives lot of attention to the vocabulary choice, as well as avoids swearing and colloquial terms. The Portuguese translator is also very careful to find strategies for the translation of reduplication and proverb, bringing aspects characteristic of the Portuguese language and, at the same time, trying to present cultural aspects of China, which did not always occur in English translationMestradoLinguagem e SociedadeMestra em Linguística Aplicad

Experimental study on characteristics of self-excited oscillation pulsed water jet

To promote the application of self-excited oscillation pulsed water jet in various fields, various characteristics of self-excited oscillation pulsed water jet were studied experimentally. A test system of self-excited oscillation pulsed water jet characteristics was designed, and it is composed of pulsed jet producer devices, particle image velocity (PIV) measuring system, pressure pulse test device and the confining pressure cavity suitable for a PIV test. The characteristics of flow field, pressure oscillation, pulsed cavitation and acoustic shock of pulsed jet were researched. The results showed that the axis velocity vector at nozzle outlet changes periodically, and gradually becomes smaller away from the nozzle. The peak pressure of self-excited oscillation pulsed water jet is 2.5 times higher than the common continuous jet. The wave crest and the wave trough of pulsed jet are not completely symmetric. As the pump pressure increases, the length of bubble cloud increases, and it first increases and then decreases with confining pressure increasing. The vibration acceleration of sonic boom increases and then decreases as pump pressure increases, and decreases steadily with confining pressure increasing

Synthesis of Vanadium Dioxide Thin Films on Conducting Oxides and Metal–Insulator Transition Characteristics

We report on growth and physical properties of vanadium dioxide $(VO_2)$ films on model conducting oxide underlayers (Nb-doped $SrTiO_3$ and $RuO_2$ buffered $TiO_2$ single crystals). The $VO_2$ films, synthesized by rf sputtering, are highly textured as seen from X-ray diffraction. The $VO_2$ film grown on Nb doped $SrTiO_3$ shows over two orders of magnitude metal–insulator transition, while $VO_2$ film on $RuO_2$ buffered $TiO_2$ shows a smaller resistance change but with an interesting two step transition. X-ray photoelectron spectroscopy has been performed as a function of depth on both sets of structures to provide mechanistic understanding of the transition characteristics. We then investigate voltage-driven transition in the $VO_2$ films grown on Nb-doped $SrTiO_3$ substrate as a function of temperature. The present study contributes to efforts towards correlated oxide electronics utilizing phase transitions.Chemistry and Chemical BiologyEngineering and Applied Science

CRaSh: Clustering, Removing, and Sharing Enhance Fine-tuning without Full Large Language Model

Instruction tuning has recently been recognized as an effective way of aligning Large Language Models (LLMs) to enhance their generalization ability across various tasks. However, when tuning publicly accessible, centralized LLMs with private instruction data, privacy concerns are inevitable. While direct transfer of parameterized modules between models is a plausible approach to address this, its implications and effectiveness need further exploration. This paper focuses on Offsite-Tuning (OFT), a representative technique that transfers transformer blocks between centralized LLMs and downstream emulators. Given the limited understanding of the underlying mechanism of OFT, we perform an empirical analysis on LLMs from the perspectives of representation and functional similarity. Interestingly, our findings reveal a unique modular structure within the layers of LLMs that appears to emerge as the model size expands. Simultaneously, we note subtle but potentially significant changes in representation and intermediate predictions across the layers. Inspired by these observations, we propose CRaSh, involving Clustering, Removing, and Sharing, a training-free strategy to derive improved emulators from LLMs. CRaSh significantly boosts performance of OFT with billions of parameters. Furthermore, we investigate the optimal solutions yielded by fine-tuning with and without full model through the lens of loss landscape. Our findings demonstrate a linear connectivity among these optima falling over the same basin, thereby highlighting the effectiveness of CRaSh and OFT. The source code is publicly available at https://github.com/TsinghuaC3I/CRaSh.Comment: Accepted to EMNLP 2023 (Main Conference